Proper locations for foundation and basement slab insulation?
If one is already planning R10 insulation outside the perimeter of the foundation wall such as Tremco’s Warm-n-Dri and their Horizon finishing system above grade, is it also a good idea to add rigid foam insulation on the inner side wall of the poured basement slab? Image is to have R10 subslab rigid insulation along with a shorter rigid insulation wall section (R10) along the perimeter of the basement slab. In other words, should the rigid be applied just outside the foundation or outside the foundation as well as the perimeter of the concrete floor. If the answer is yes to around and under the slab, how should the rigid pieces intersect … lay the side wall section on top of the sub slab section or along side of it? Is that detailed section available somewhere on the site? Is it preferable to spec XPS or a higher density EPS rigid product for that application?
GBA Detail Library
A collection of one thousand construction details organized by climate and house part